The general aim of the Regulations is to provide ade­quate standards of safety to protect people, property and the environment from the hazards of radioactive material. It is also desirable that packages should be moved with the minimum of delay and that require­ments for special actions by the carrier are minimised.

The Regulations are written in such a form that they can be incorporated into national legislation. They prescribe what has to be done, rather than how or why it is done, the latter aspects being subjects for sup­porting documents [13,19].

As far as possible, the required protection is af­forded by package design and contents control, so that in general the carriers’ responsibilities are limited to segregating and limiting the numbers of packages on conveyances and during in-transit storage.

Adequate protection has to be provided against external radiation from packages, and human intake of any radioactive material on or escaping from the package under both normal and accident conditions. In addition to prescribed limits on dose and dose rate [14], the general principle that radiation exposures shall be kept as low as reasonably achievable (ALARA) applies.

l or packages containing fissile materials, precau­tions are required against criticality, with exemption in a few cases under specified conditions.

Arrangements must be made for adequate dissipa­tion ot heat from packages.